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· A short fat well off crap cave diver. Likes wrecks
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Discussion Starter · #1 · (Edited)
The Delta Diaries, A couple of good wrecks and a few cock-up's.

Dive1

Surprisingly, I had to wait till the 7pm forecast to see if the dive was on. I had been told to prepare for a deep one with the wreck apparently at 75m. I was having fun with my mini-booster so the 16/50 I had managed to cobble together would have to make do.

5am leave and a cruse down to Little Hampton to be told its probably going to be a little rough so we canned the plan and were going to have a look at the Donegal in 50m. If the viz is no good we would move on to the German wreck in 65

Ho hum, thank God for the flexibility of CCR.

As it turned out the worst we faced were waves of about a foot so I think Ian McGaskle did the forecast

Today I was to meet Dave R for the first time, A Portsmouth based diver on a KISS unit. Dave was a DIR diver way back in the early days but he’s since moved on to diving a Sports KISS. I asked him why? He said the gas cost of OC and deep wrecks just didn’t work so they couldn’t fill the boats. I liked him instantly :D

His tanks were marked up with his initials DIR which I found most amusing. Do you think he’s the only diver ever to go DIR because his name tags matched :D

Dave mid pic.



The viz on the Donegal looked doable so we settled in to wait for slack water.

Dave agreed to lay the line and I was going to take pics but the day was badly overcast and viz on the Donegal is usually poor due to its location near a river estuary, so in the end I changed my mind. I should have opted to lay the line today but I didn’t and this was going to cost me tomorrow

The Donegal was built in 1885 and sunk by torpedo via UC21 in 1917 with the loss of 11 soles. At the time she was in service as a hospital ship.

Dave and I dropped in third to find 5-6m of viz with stringy plankton clumps. All in all very doable. We mozied along up to the bow having a good look see and I found a nice 4-5lb lobster for the wife God and wasted no time bagging it up. We found the chain locker and to the right I found a monster valve looking thing. It was bell shaped with a knob on one end and a cut out showing the internals. It looked really interesting and it looked to be brass but I decided it was too big a task and I wasn’t sure what the hell I would do with it anyway so I left it.

Dave pulled out his trusty DIR mini knife from the webbing sheath to cut the guide line and I laughed my arse off when he emerged with just a handle as the blade fell off.
I got my knife out and cut the line for him and we headed back to the shot. On rout I found the kitchen. There were four or five massive pots. It amused me to think they could be copper and worth the tight squeeze in to grab one but the squeeze was a little too tight and my desire was not strong enough to spur me on to more wiggling. Then at the last I found a massive porthole. It must have been 600-800mm across with intact glass and brass backed. It looked gettable and I had a quick go but we were out of bottom time and I was aware Dave was on tables so I didn’t want to mess up his plan on our first dive so I made a good mental note of where it was and left it for next time.

Deco was deco and we headed home on flat sea and in warm sunshine. It was a pleasure to dive with Dave he just did everything the way I like it. Nice and slow and predictable.

I followed Dave's deep stops to stay in touch which added 9 mins to my overall time. Hears the graph for anyone whos interested.




Tomorrows wreck sounded really interesting. The Doctor was all excited about it which is a good sign :D

ATB

Mark Chase
 

· A short fat well off crap cave diver. Likes wrecks
Joined
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15,284 Posts
Discussion Starter · #2 · (Edited)
Day2.

Up at 5 again and it is lashing down with rain and dark as hell. Fortunately the early morning divers are hard core and the traffic hadn’t been slowed too much by conditions and I made it to Little Hampton OK. Once there things looked much nicer but a monster cloud burst hit us soon after getting the kit on the boat.

Sea conditions were apparently going to be crap so the long range plan was canned again and we were going for the 65m banker wreck the Polandia. I can’t tell you much about her (we arent even sure of the name) as we haven figured it all out yet but it’s a steam ship from around the turn of the century. Kit was lashed down tight and we sat in harbour for over an hour because it was only a 20mile run out.

Janos had joined us today and this was to be his deepest CCR dive. Graham hadn’t made it so it looked like Janos Dave and I would be diving as a three. Janos and Dave’s exposure to DIR was going to come in handy.

I decided to take the camera in with the strobe for the first time. It’s a large and ungainly set up and of course like a twit I had opted to lay the line today as well. Dave did it yesterday and Janos was about to do a deep dive with an unfamiliar teem so I wasn’t going to ask him to do it.

The rain stopped and we set off into the cruel and unforgiving sea to be faced with flat calm conditions?? This was unbelievable. The 4-5 forecast wasn’t even a 1. I have to say I was feeling pretty pissed off that we missed two golden opportunities to go exploring but sod it the Polandia and the Donegal are fine wrecks.

On rout we picked up a very tired passenger:



A very casual cruse out got us on site nice and early and again my lot were third in. We hit the bottom of the shot and conditions looked 5-6m so I tied off the line on what is a very ship shaped wreck and usually easily navigable. As soon as we were 5m from the shot the viz cleared to a good 10mand we found ourselves directly over the china room.

I had planned to go in search of a porthole for Janos and do the china on the return leg but having the shot so close to it I felt it likely that the others would have a go too on the way back and I wanted to take a pick before they started routing around in the silt for the good stuff.

Janos grabbed a large platter which we set aside for collection on the return leg and I tried to take pictures but the camera strobe was playing up so they didn’t come out. I think Dave tolerated our spidging but wasn’t really into it so we were soon heading away from the china and on to the lamp locker.

On rout we came across the biggest lobster I have ever seen. I reckon 12lb+ with its main cutting claw at least the length of the 21W salvo torch head it was trying to bite.

Sorry for crap pic but the flash wasn’t having any of it.



We carried on and Dave and Janos had a great time mooching over the wreckage. I was having a foul time trying to stop the camera getting tangled in the guide line and vowed never to lay line and take a camera again. Fortunately viz was excellent so I just cut the line and carried on by pilotage.

On the return leg we once again visited the China room and I tried to grab another platter to match Janos and I got a lovely little coffee cup as a memento. With 40mins showing we headed to the Shot and Dave was already on the ascent. I tried to quickly bag up the china but the tide was running hard and Janos and I were struggling with the small spidge bag so I gave up at min 44 and signalled Janos to ascend. I cut the waster and we headed up Janos carrying a very large platter and me with a goody bag full of china. This made things a tad awkward but I decided to leave sorting it out till the first stop. We hit the 42m stop and Janos gave me the feeling dodgy sign and requested a bubble check. I couldn’t find anything wrong with his unit but I took the platter off him and eventually squeezed it into the goody bag.

Just in time as the shortly after Janos was a flurry of activity and he’d bailed out to OC. We were face to face and I could see he was doing OK so I checked his loop to see if there were bubbles coming from the mouthpiece. It all looked OK and Janos looked amazingly calm and he had switched his Shearwater to OC OK so we carried on the ascent.

I unclipped the station at 32m and at last we were out of the drag of the tide and free to hang mid water. At 21 Jnaos switched to 50% no problem and I watched him check the Shearwater again. I turned my 50% on and made sure the reg was available for him if needs be then tried to figure out how to get rid of the china.

Dave was with us and playing a watching brief so I decided to drop off the line and fin away clear of the up line so I could bag up the china. I decided to use my mini C02 blob to lift it but this turned out to be a mistake twice over.

I cracked the bottle which might have been adequate to send up the SMB but it didn’t lift the china. I was faced with having to use the air line mid water so I had a think about it and decided to have a go. In the end it went off OK and I was pleased to be free of the heavy goody bag. I went back over to Janos to resume my watching brief.

I checked his gas and there was no way he was going to finish deco on the 7ltr of 50%. Sure we had my Ali80 but I decided to send for the drop tank. I showed Janos the yellow bag and signalled the intent and I waited for the 9m stop before sending up the bag.

John came over and assessed the situation and signalled me to send up the bag now. So I went out into the blue again and sent it up. 10mins later a 10ltr of 70% was on its way. It felt a long time before we got the tank but apparently me sending up spidge on a SMB had confused the boat into thinking they had a drifting diver so this delayed things a tad.

In the end the tank appeared and I went over to drag it back to the station. I was surprised at it being only 70% I was expecting the tank of 100 but it would do the job so Janos switched and reprogrammed his Shearwater.

Mean time I had had a CNS warning on my unit. All my fafing around had resulted in me running a high PP02 on ascent and I had left it to drop by its self and ended up with 100CNS with a fair bit of deco left to do.

I dill flushed down to 0.8 and staid there for a while before slowly bringing it up to 1.6 for the final leg of deco.

Janos was now happily loaded with gas and resigned himself to the deco commitment buffered by the music on his MP3 player.



Oh and any one who thinks steel 10s don’t float. Check out the pick of the 10 with 70% in.


Deco done and back on the boat we were presented with the bill for the gas and a document to sign admitting to our muppetry. The hand writing wasn’t easy to read so I have no idea what I have counter signed but I believe it involves me being a twat for sending up spidge on a SMB.

I asked why we were sent the 70% instead of the tin of 100% and Don John turns round and said F#ck me Mark he’s only a guest, he doesn’t deserve the good stuff :D

I think to be honest they realised we weren’t on the 6m bar yet (they could have seen us if we were) so they felt we might need the gas breathable deeper than 6m :D

Janos spent a few mins analysing the totally flooded scrubber on his kiss and explaining that the unit had gurgled a bit but on the ascent he lost all ability to breathe out and started to taste a hint of sodalime so he bailed.

Then he spent the rest of the trip going on about how great the dive was.

This was Janos deepest ever dive and I have to say he was incredibly composed and competent throughout the little adventure. Many divers faced with two hours deco and bailing out would no doubt have been less calm and collected. I am now 100% convinced that in Janos case at least having both tanks left was in no way a hindrance to bailing out. He did it quickly and without undue fuss.

Well done M8 I think I was more scared than you were :D

ATB

Mark Chase
 

· A short fat well off crap cave diver. Likes wrecks
Joined
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15,284 Posts
Discussion Starter · #16 ·
Hi,

Janos, what caused the flood do you think? What were the symptoms, effects and at what point did you think, I can't salvage this, and bail out?

Dave C
I cant answer the first bit but I know the answer to the second, he couldent breath out on loop.

So semi closed as an option is out O2 rebreather is out its bail out to OC and do alllllll the deco OC.

ATB

Mark Chase
 

· A short fat well off crap cave diver. Likes wrecks
Joined
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15,284 Posts
Discussion Starter · #20 ·
Out of interest and if you missed it on RBW: All these on a 20SAC


58mdive for 60mins bailout plan. Just 660 bar required in a 7ltr of 50% and 250 bar of 18/45 :D



Hear is my actual bailout plan for a 45min dive to 65m using an Ali80 and a Steel10 and running a 125%GF :eek:



Here is a plan for 35mins at 45m using a single 7ltr of 32% as bailout and running normal deco 20/80GF 350bar required.



It makes you think when you sit down to do the math :D
 

· A short fat well off crap cave diver. Likes wrecks
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15,284 Posts
Discussion Starter · #25 ·
Mark

Have you ever had a dive in a pot just to get used to the environment?

Don't quite understand the question here?


How do you intend to bailout at the end of said 45min 65m dive? especially as I personaly think your being incredibly optomistic thinking your going to retain a 20l/m SAC rate for at least the the first 10 mins after a CO2 hit.

My normal SAC for deco is 8-10 I anticipate bailing out (Via BOV) long before my SAC hits 40 and i have 10ltrs of 18/45 to eat before I get on to the 50%. The 10/120GF plan is going to be more like 50/120 if i am short of 18/45 but by the timevI have finished a 10ltr I should have my SAC under control. So planning on 20 I have a 100% safety margin.

I know you have a team on the station but what if you can't get back? At the speed you could be chewing through gas getting back to the shot might just be out of the question. maybe the reason you've had a CO2 hit is because the tide has suddenly changed and your swiming in to the current.
I'm very interested as I've always though your calcs were a little on the alpine side but now I'm starting to go past 60 and reworking my bail out I'm interested in every one's opinion and the scenarios they would run.

Simple truth is if your going to do this sort of dive you have to have a serious base line and this plan is it. This plan assumes I have no option on semi closed, no buddy, I cant find the shot, no drop tank and no option to go pure 02 rebreather @6m

Its a reely reeeeeelllly bad day when I have to use it, but I plan for just such a day coz sh#t happens when you go diving.



Janos experiance has just helped reinforce my view that loop integrety can not be relied on so even down to just using it as an o2 rebreather or going SCR in my opionion are too much of a risk. I'm not happy to rely on team bail out as that would mean I'd have to have one but I would use a drop tank on the boat, possibly even 2 say a 50 and a 100 or I'm also about there on a side slung KISS just looking for a suitable mouth piece.

All correct in my view.

I hope you take this in the way it's ment and you don't take offence may be we could have a chat about it some time as I know you'll have researched it to the fullest.

Fin
No problem at all M8.

I accept that using my OMG bailout plan and assuming multiple cluster situation actually occurred in the very last seconds of a dive (as it did for Janos) id more than likely be bent. I do not, however expect to be in a wheel chair or dead.

Bent is an acceptable level of risk for me but wheel chair or dead is not.

Remember that under 95% of conditions I could happily complete my normal deco on this dive with the options available to me as part of the group.

The above knowledge stops me doing 60mins at 65m regardless of how good the dive is, and encourages me not to push it to the max (45mins) when the dive is average or I have an equipment concern.

ATB

Mark Chase
 
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· A short fat well off crap cave diver. Likes wrecks
Joined
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15,284 Posts
Discussion Starter · #26 · (Edited)
So what is that program called Mark?

I've just done an Excell Spreadsheet based on Paul C's bailout tables for the volumn of bailout I would need. Now I'm not advocating the tables as I don't know exactly how he did them but I think I did the calulations for the bailout right.

Mark, you could run a comparison on your GoPram and let me know how I'm doing:

Dive1:
[1.3 setpoint] Air Dil, Air Bail out.
40m for 30 mins. Stops at:
21 - 1
18 - 2
15 - 2
12 - 3
0.9 - 3
0.6 - 3
0.45 - 10

This with a SAC of 30, this leaves me needing 675 ltrs to 21m (3mins travel time, incl bailing out), 1101ltrs for the stops (total = 1776 ltrs => 9ltrs @200 bar fill) ~10ltrs cylinder of Air

(Please Bare in mind I'm not asking for a discussion of the bailout deco table and stops. Just give me an idea of the amount of air I need to get to the surface given the times listed. I can change the deco table as and when I do one myself, given any advice separately later) (also I'm an Air Dil diver and can't use Trimix for deco. Also lets assume I have one gas - AIR.)

Dave C

Running normal deco (20/80) on a 30SAC for bailout




A quick fiddle with the numbers to get your deco time gives 5/110GF deco. Pretty agresive stuff.
 

· A short fat well off crap cave diver. Likes wrecks
Joined
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15,284 Posts
Discussion Starter · #30 ·
The chamber bit is a bit like you take your 4 year old to school for a morning so when they're 5 and have to go every day they are not scared of the place. Joking aside every should take the opertunity for a dry dive and then if required for treatment then the whole experiance is less traumatic.
At the end you do state it's a plan which will get you to a chamber not one that will get you to your car and driving your self home . Sorry I did not understand that as I though I recalled a chat with you some time ago saying you'd not accept that leval of risk.

There must be some misunderstanding here between aggressive deco and bailout. I don't do aggressive deco, I cant see the point. Aggressive bailout is something I hope i never have to do but I know its there as my baseline and bent is always better than dead. The bit that worries me more is wheelchair so id rather have a structured plan for the deco with some hope of minimal damage rather than just guess.

I have done table 6 in the pot twice but I don't know that it prepared me for any diving. If anything it built up my confidence running high CNS numbers but apart from that you sit in a chair breath and get bored.


I still think the sac calculations are a little optimistic for me but i hope you a. never have to find out and b. are correct but yep they'd get you to the surface with probably enough deco to not be too uncomfortable while awaiting the chopper.
My SAC calks are based on hundreds of hours of decompression on OC. My deco SAC was always between 8-10lpm. My plan is to bailout early before my breathing rate gets daft and chill out on the 10ltrs of 18/45. I may start the bailout on 40sac and have to blow off some deep stops to conserve gas, but by the end of the 10 I hope to be down to below 20 for the important switch to 50%

Per haps we could meet and discuss some time as I'm sure you given this lots of though (as always).
Love too.


Thing is its just thought. I plan and plan again and I take great comfort from knowing what my options are. Whether or not it will actually work in practice is something you cant train for. You have to experience it for real.

Like Janos bailing to all tanks left. I didn't think that would be easy but he proved me wrong by actually doing it. I wouldn't have believed it till I saw it in a proper high stress situation.

I was wrong he was right. I may be wrong with my worst case plan but at least I have a plan :D

ATB

Mark Chase
 
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